In this blog post, we’ll explore how materials engineering—the foundation of nearly all technology in our daily lives—has contributed to human civilization and technological advancement.
The term “materials engineering” may sound unfamiliar to some. When most people think of engineering, they tend to think of mechanical engineering, biotechnology, or architectural engineering, and it seems they view the words “materials” and “engineering” as an unlikely pairing. However, research on materials is undoubtedly one of the most essential fields for human life. Almost every object we use in our daily lives is a product of materials engineering. From the plastics used in household appliances to the steel that supports building structures and even car engines, all of these are underpinned by research and advancements in materials engineering. Today, we encounter and use objects made from a variety of materials that were unimaginable in previous eras. In this post, I’d like to introduce materials engineering—a field that has transformed the environment in which humanity lives, often without most people even realizing it.
It is said that about 3,000 years ago, when Solomon completed his palace in Jerusalem, he asked who had contributed the most to its construction. The first to speak was a bricklayer, who claimed that every single brick he had made had helped create the beautiful palace. Next, a carpenter stepped forward, claiming that he—who had laid the foundation before the bricks were laid—was the one who had made the greatest contribution. After hearing both men, Solomon is said to have asked, “Then who made the tools used to make the bricks and shape the wood?” After saying this, Solomon is said to have respectfully offered wine to the blacksmith, who had been standing silently with a face blackened by soot.
This story conveys an important lesson. The palace in Jerusalem would not have been completed without the blacksmith, who, though he did not take on any conspicuous or glamorous tasks, quietly carried out his work. Today, some 3,000 years later, we can find common ground between the blacksmith in this story and the field of materials engineering.
The first commonality is that they serve as the foundation for advancements in other engineering fields. Today’s space exploration is made possible by the development of materials that remain strong even when exposed to intense heat. Furthermore, it is no exaggeration to say that the revolution in the information and communications sector was brought about by advancements in semiconductor materials. In this way, countless developments in engineering have required the prior development of the materials used in those fields. Foldable smartphones, which have recently become a hot topic, and solar cells—presented as one of the alternatives to eliminate the risks of nuclear power—are all part of the field of materials engineering. Furthermore, various cutting-edge technologies, such as electric vehicle batteries, artificial organs, and superconductors, are being realized through the power of materials engineering. In other words, most news we hear about advancements in engineering fields is essentially news that the development of suitable materials to make them possible has been achieved.
The second commonality is that the work of a blacksmith—specifically, the pursuit of creating strong iron—resembles the efforts in today’s materials engineering field to create even stronger materials. You may have seen scenes in historical TV dramas where a blacksmith dips iron heated over a charcoal fire into water and then hammers it. If we examine the principle behind this, it is a surprisingly scientific method—one that people understood some 3,000 years ago. The arrangement of atoms in iron, or its structure, changes depending on temperature; the most dense structure is not found at room temperature but at high temperatures of around 900 degrees Celsius or higher. In other words, the internal structure of the red-hot iron the blacksmith works with is more densely packed, with atoms arranged without gaps. Furthermore, the carbon atoms emitted by the charcoal fire are smaller than iron atoms, and these carbon atoms actually squeeze into the gaps within the iron’s internal structure. When the most dense structure is formed, even these small carbon atoms become embedded, acting as a sort of adhesive. When iron heated over a charcoal fire is placed in water and rapidly cooled, the iron atoms, which had formed a dense structure, freeze in place as they attempt to revert to their room-temperature structure. Because the cooling process is extremely rapid, the iron atoms can only move a short distance during that time; consequently, they freeze into a structure that is stronger than the one they would naturally form at room temperature. The iron obtained in this way has high hardness but is brittle; blacksmiths address this by hammering it at an appropriate temperature to impart ductility—the property that makes it resistant to breaking. Of course, today’s methods differ from those of the blacksmith, but broadly speaking, they still rely on the same principle. Just as blacksmiths did thousands of years ago, researching the process of creating strong materials remains a crucial aspect of materials engineering.
Today, materials engineers have already developed materials that are hundreds of times stronger than the iron produced by blacksmiths, yet much lighter. These innovations extend far beyond simply strong materials to include materials that generate electricity when exposed to light, materials that do not melt even at temperatures of thousands of degrees, and materials that can serve as substitutes for human bone. Innovative new materials are being researched across such a wide range of fields that it is difficult to imagine the limits of materials engineering. These innovations are inextricably linked to technological advancements in modern society, and their scope is vast. For example, from electric vehicles and solar panels to semiconductors designed to process artificial intelligence computations more rapidly, all technological advancements are closely tied to the development of suitable materials.
Just as King Solomon, the wise king of over 3,000 years ago, did, I hope that many people will come to take an interest in the field of materials engineering, which forms the foundation of all innovation.
